What Is a Rotary Engine? Definition, Meaning and Concept

The rotary engine is a type of internal combustion engine with a substantially different design than the much more common piston engine. In a conventional piston engine, a spark plug ignites a mixture of fuel and compressed air in a closed chamber, causing the superheated gas to expand rapidly. Repeating this cycle causes the characteristic up-and-down motion of the pistons in an engine, which is converted into a rotational motion used to drive the wheels of a car or the propeller of an airplane or ship.

First conceived by German engineer Felix Wankel in the early 1920s, the rotary engine consists of a rotating triangular component embedded within an ovoid casing. The apexes of the triangle form a seal against the casing, creating three isolated chambers, which collectively perform the four basic functions of any internal combustion engine: intake, compression, ignition, and exhaust. As the triangle rotates, the three isolated chambers also rotate, allowing a given volume to be exposed to an intake valve, spark plug, and exhaust port as they rotate through the interior of the rotary engine.

In the first stage, a fuel-air mixture is injected into a pocket created between one edge of the triangle and its oval casing. The triangle rotates inside the rotary engine until the seal isolates the fuel volume from the intake valve and exposes the fuel to a spark plug. The spark plug fires, igniting the fuel-air mixture, which expands rapidly and causes the rotating component to rotate, driving a crankshaft. In the final phase of the rotation, the expanding gases escape through an exhaust port, and the volume is now free again, allowing it to receive more fuel from the intake port and repeat the entire process. Each of the three volumes is alternately injected full of fuel, which is then burned and then exposed to an exhaust port.

Although the Wankel rotary engine is theoretically more elegant than a piston engine, and requires fewer moving parts, the wear caused by the rapidly moving triangle apexes inside the rotary engine casing has proven unacceptable to most car companies. that consider creation. of production models. Today, Mazda is the only company that continues to sell cars that use rotary engines. Fundamentally, the idea of ​​an engine that replaces the jerky up-and-down motion of a reciprocating piston engine with a smooth rotary motion is quite appealing, but practical considerations have so far prevented them from displacing the conventional engine. Perhaps with the introduction of new materials or knowledge,